Improvement in master-key devices for post-office boxes



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UNITED STATES PATENT OEEIGE;

HENRY R. TOWNE, OF STAMFORD, CONNECTICUT, ASSIGNOR TO THE YALE LOCK MANUFACTURING COMPANY, OF SAME PLACE.

IMPROVEMENT IN MASTER-KEY DEVICES FOR POST-OFFICE BOXES.

Specification forming part of Letters Patent N0. 206,646, dated Jnly 30, ISTS application filed July 8, 1878.

To all whom 'it may concern:

Be it known that I, HENRY R. TowNE, of Stamford, in the county of Fairfield and State of Connecticut, have invented a certain new and useful Master-Key Device and I do hereby declare that the following is a full, clear, and exact description thereof, which will en able others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters of reference marked thereon, which form a part of this speciication.

The object of my invention is to provide a series of doors or lids with a device which will enable one key to be used to lock and unlock all of the doors or lids, while at the same time every door or lid may be locked or unlocked by its own key, which will control no other door or lid of the series. This latter key I call the change key.

I am aware that locks have for a long time past been constructed so that all of a series could be opened by one master-key, and yet the proper or change key of none of the locks would open any other of the series. The defects of all previous systems have been, however, that the number of locks which could be thus made to be opened by a lnaster-key, while each lock had a distinct key of its own, was limited; and, further, the construction of each lock so as to be opened by two different keys seriously impaired its security against picking and its capacity for permutations.

My device obviates all these defects. Vith it the number of doors or lids which, while each has a separate key, can be ttcd to be locked and unlocked by one master-key is only limited by the number of permutations of which the particular bolt-actuating mechanism used is capable, while the security against picking is in no way affected and the capacity for permutation remains as before. By using the bolt-actuating mechanism of the Yale lock, which I prefer, tty thousand or more doors may be thus fitted, if desired. I accomplish these results by separating the mechanism by which the master-key actuates the bolt from that by which the changekey actuates it, the device being so constructed that either key, through its own intermediate mechanism, will actuatc the same bolt.

It will be seen that what maybe termed the master-key mechanism of my device may be made identical on any number of doors or lids, so that the same key will control them all, while the change-key mechanism may be varied to any extent of which the system on which it is constructed is capable.

The construction and operation of my de vice may be clearly understood by reference to the accompanying drawings, where similar lletters of reference indicate corresponding parts, and in which- Figure lis a front elevation of two boxes to which my device is applied. Fig. 2 is a vertical section 011 line y of Fig. 1. Fig. 3 is a plan showing one ot` the doors open. Fig. 4 is a rear elevation of the boxes. Fig. 5 is a vertical transverse section on the line 5 5 of Fig. 6, showing a mortise-lock to which my device is applied, so that the bolt may be operated from either side. Fig. 6 is the lock shown in Fig. 5 with cover removed, showing operation of my device in the lock.

A A are the doors. B B are the door-frames. C C are the sides of the boxes. D D are the bolt-actuating mechanisms, of which no two can be operated by the same key. Dl D are the bolt-actuating mechanisms, all of which may be operated by the same key. E E are the bolts.

The construction ot' the boxes and doors shown in the drawings need not be explained, as that is not of this invention.

The bolt E, as shown in Figs. 1, 2, 3, and 4, is thrown forward by a spring, thus automatically locking the door when it is shut, while in Figs. 5 and 6 the bolt is both cast and retracted by the key. Connection between the keys and the bolts is made, as shown in thc drawings, by means of rotating plugs, to which are rigidly connected pins or cams.

When a key is inserted so as to set the tum blers and rotate any one of the plugs its pin or cam will engage with the bolt E and cast or retract it.

Now, suppose a series of any number ot doors or ot' locks, as shown in the drawings, whose bolts may cach be actuated by either ot' two independent key mechanisms-it is evident that if on every door or lock the actuating mechanisms D be so constructed that one key will operate them all, while the actuating mechanisms D be so constructed that the key of any one will operate no otlier,tl1e person who has a key to operate the mechanisms 1) can open all the doors, while a person who has a key to operate one otl the mechanisms 1) can open but one door of the whole series.

I do not eonne myself to the partienlar holt-actuating mechanism here shown, as that is not of this invention; hut

What I claim, and desire to seenre hy Let` ters Patent, is-

A series 01 set of doors, lids, or locks, each of which is provided with a leek-holt controlla- Witnesses:

SeHi'YLER Mrmmrr, (me. ll. SMITH. 

